At first I had a lot of problems with this. I'd get an error every time I attempted to render, it would take forever to load saved files etc. I've got the new beta and things are running better. However, it seems that heavy use of shaders still causes it to crash, and I can't render files from previous versions. The beta is much more stable, however, and I'd advise upgrading to it if you HAVE to go to 2.2. You can access it off a link on their forums.